thesaurus is finally working... It contains recursive entries to parnet
term, and we actually needed to display narrower terms, so mem_lookup was
created. Important changes:
- you can write eval{"901a" eq "Mikrotezaurus"} within <isis>
tag and if expression evaluates to false, no content will be outputed
(It's used to hide microtesarus terms from lover level descriptors)
- mem_lookup.pm now supports formats: you can write something like
[a:5614];;[d:[a:5614]] and it will correctly embed values